Vibration Stop Device

ABSTRACT

An object of the present invention is to provide a configuration of a vibration stop device that can prevent a problem caused by intrusion of a pressure contact region of a holding part of the vibration stop device into a recess of processing region of a work. 
     The object can be achieved by the vibration stop device, in which a plurality of holding parts for vibration stop holds an outer circumferential surface of a columnar work in a process stage under a pressure contact state with pressure supplied from a hydraulic cylinder, and a pressure contact position on the outer circumferential surface is changed by rotation of the work, wherein an angular range formed by both ends of each of the holding parts for vibration stop is larger than an angular range of the processing region regarding an angular range based on a position of an axis of the rotation.

TECHNICAL FIELD

The present invention is relates to a vibration stop device necessaryfor stopping vibration of a work in a process stage.

BACKGROUND OF THE INVENTION

Accurate processing on a work in a process stage requires the work to beprevented from vibrating.

The work is divided into a processing region and a non-processing regionalong a circumferential direction, and in many cases, moves togetherwith a main shaft in a state where a holding part for vibration stop isin pressure contact with an already processed region of the work.

As shown in FIG. 5, in the pressure contact state of the holding part ofa prior art, a pressure contact region is too small. Thus, it cannot beavoided to make a partial region of the holding part come into pressurecontact.

On the other hands, the pressure contact state causes a problem that thepressure contact region of the holding part intrudes into a regionrecessed by the processing, in the other words, in a recess, and even ifthe work is to be rotated along a columnar center axis for the nextprocessing, such rotation is hindered due to the intrusion.

However, in the prior art, no particular countermeasure has been takenfor the problem caused by the pressure contact region of the holdingpart intruding into the recesses that has been formed by the processing.

For reference, Patent Document 1 describes, regarding a camshaft work tobe ground, a processing region and vibration stop for the work,nevertheless has no particular description on the relationship betweenthe processing region and the vibration stop.

Patent Document 2 describes both processing on a work and a vibrationstop device, but does not describe the problem arising when the pressurecontact region comes into contact with the region that has already beenprocessed.

PRIOR ART DOCUMENT Patent Document

Patent Document 1: JP 2005-169530 A

Patent Document 2: JP 2010-99746 A

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

An object of the present invention is to provide a configuration of avibration stop device that can prevent a problem caused by a pressurecontact region of a holding part of the vibration stop device intrudinginto a recess of a region that has been processed.

Effect of the Invention

To achieve the object, the present invention has the following basicstructure:

A vibration stop device, a plurality of holding parts for vibration stopholds an outer circumferential surface of a columnar work in a processstage under a pressure contact state with pressure supplied from ahydraulic cylinder, and pressure contact position on the outercircumferential surface is changed by rotation of the work,

wherein an angular range formed by both ends of each of the holdingparts for vibration stop is larger than an angular range of a processingregion regarding an angular range based on a position of an axis of therotation.

In the present invention having the basic structure, the pressurecontact region of the holding part of the vibration stop device neverintroduces into the recess in the processing region, and so, the problemin the rotation of the work due to the intrusion can be prevented.

Moreover, in the examples described later, the position of the holdingparts can be independently adjusted, whereby the precision error of thework can be easily corrected.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side cross-sectional view of a first embodiment.

FIG. 2 is a side cross-sectional view of a second embodiment.

FIG. 3 is a side cross-sectional view of a third embodiment.

FIG. 4 is a side cross-sectional view of a vibration stop device of anexample 1, and also includes a block diagram showing a configuration ofan oil pressure supplying device of an example 2.

FIG. 5 is a side cross-sectional view of a configuration of a vibrationstop device of the prior art.

DETAILED DESCRIPTION

As described in the basic structure, the present invention has a featurethat, regarding the angular range based on a position of an axis ofrotation of a columnar work 2, an angular range formed by both ends ofeach of a holding part for vibration stop 11 is larger than an angularrange of a processing region 21.

The basic structure can be embodied in a number of ways. FIGS. 1 to 3show typical embodiments.

FIG. 1 shows the first embodiment having a feature that a holding parthas an arc shaped surface on the pressure contact side, and a radius ofcurvature of the arc is the same as the radius of the work 2.

In the first embodiment, pressure contact can be done mainly at anon-processing region 22.

Of course a holding part for vibration stop 11 never intrudes into arecess of the processing region 21 that has already been processed.

FIG. 2 shows the second embodiment having a feature that the holdingpart for vibration stop 11 has an arc shaped surface on the pressurecontact side, and a radius of curvature of the arc is larger than theradius of the work 2.

FIG. 3 shows the third embodiment having a feature that the holding partfor vibration stop 11 has a flat surface on the pressure contact side.

In the second and third embodiments, the surface of the holding part forvibration stop 11 on the pressure contact side might come into contactwith or come close to a surface of the processing region 21, as shown inFIGS. 2 and 3. However, also in these embodiments, as shown in FIGS. 2and 3, the holding part for vibration stop 11 never intrudes into therecess of the processing region 21 as in the first embodiment. This isbecause the angular range formed by both ends of each of the holdingpart for vibration stop 11 is formed to be larger than an angular rangeof the processing region 21.

As shown in FIGS. 1 to 3, in each of the first, second, and thirdembodiments, a pair of the holding parts for vibration stop 11 comesinto pressure contact with both sides of the work 2, and the two sidesof the work 2 are rotatably connected to the pair of the holding partsfor vibration stop 11, and a pressure transmission part 12 which isinterlocked with a single hydraulic cylinder 31 is provided, such thatapproaching and separating of the holding parts for vibration stop 11 toand from the work 2 are achieved by changing oil pressure.

In the first embodiment, even when the entire processing region 21 isformed into the recess as shown in FIG. 1, the holding parts forvibration stop 11 are in pressure contact with both sides of thenon-processing regions 22 and at least four pressure contact regions areformed. Thus, unlike the conventional technique shown in FIG. 5, theholding part for vibration stop 11 for directly transmitting the oilpressure from the hydraulic cylinder 31 is not required to be providedin addition to the holding parts for vibration stop 11 for sandwichingthe work 2 from both sides.

However, in the second and third embodiments, as shown in FIGS. 2 and 3,the holding parts for vibration stop 11 are not necessarily in pressurecontact with both sides of the non-processing regions 22. When the depthof the recess of the processing region 21 is very small, the pressurecontact is made on two positions of the processing regions 21, and sothe pressure contact state is achieved at substantially two points.Thus, as shown in FIGS. 2 and 3, the third holding part for vibrationstop 11 that directly presses and comes into pressure contact with thework 2 by the pressure from the hydraulic cylinder 31 may be provided.

The first embodiment does not require the third holding part forvibration stop 11, and thus can achieve a simpler design and lower costcompared with the second and third embodiment.

However, the first embodiment requires the holding parts for vibrationstop 11 having radii of curvature respectively corresponding to thevarious radii of the works 2, and thus is more cumbersome than thesecond and third embodiment in this point.

Examples are described as follows:

EXAMPLES Example 1

As shown in FIG. 4, the example 1 has a feature that the holding partsfor vibration stop 11 are each independently interlocked with ahydraulic cylinder 31, and approaching and separating of the holdingparts for vibration stop 11 to and from the work 2 are achieved bychanging the oil pressure.

When a precision error occurs in the work 2, the pressure contact statecreated by a vibration stop device needs to be immediately released, andthe processing region 21 where the precision error has occurred needs tobe rotated to an operation position on a main shaft side.

In such a case, the conventional technique shown in FIG. 5 and theembodiments shown in FIGS. 1 to 3 require cumbersome control such as anoperation of the pressure transmission part 12, and movement of thethird holding part for vibration stop 11.

In the example 1, the rotation state can be achieved by immediatelyreleasing, from each of the holding parts for vibration stop 11,pressure supplied from the hydraulic cylinder 31, and the precisionerror can be quickly corrected.

In many cases, a number of the holding parts for vibration stop 11 and anumber of the hydraulic cylinders 31 shown in the example 1 are eachthree.

Example 2

As shown in FIG. 4, the example 2 has a feature that a relief valve 34is provided in juxtaposition with the solenoid valve 33 which suppliesthe oil pressure to the vibration stop device, in a hydraulic circuitthat creates the pressure contact state.

Specifically, a hydraulic cylinder 31, a pressure reducing valve 32 foradjusting the pressure, and the solenoid valve 33 for turning ON and OFFtransmission of reduced pressure are used as in the conventionaltechnique, and the relief valve 34 in parallel with an oil pressurecircuit is further provided.

In the example 2 described above, even if the vibrating state of thework 2 is changed and consequently the amount of pressure required forthe pressure contact of the holding part for vibration stop 11 changesby turning ON the relief valve 34, the change in the pressure can becompensated by the relief valve 34 turning on, so that the pressuretransmitted to the hydraulic cylinder 31 can be reduced as much aspossible.

APPLICABILITY OF THE INVENTION

Thus, the present invention can achieve the vibration stop without theproblem of intrusion into the recess of the processing region, and canquickly correct the precision error, and thus is extremely useful.

EXPLANATION OF REFERENCE NUMERALS

-   1 vibration stop device-   11 holding part for vibration stop-   12 pressure transmission part-   2 work-   21 processing region-   22 non-processing region-   3 oil pressure transmission device-   31 hydraulic cylinder-   32 pressure reducing valve-   33 solenoid valve-   34 relief valve-   35 oil pressure supply part

1-8. (canceled)
 9. A method of stopping vibration of a columnar workduring processing of the columnar work, the method comprising the stepsof: dividing an outer circumferential surface of a columnar work into aprocessing region and a non-processing region in a process stage of thecolumnar work, with the non-processing region having a radius ofcurvature, providing a vibration stop device including a plurality ofholding parts, with each holding part having an arc shaped surface on apressure contact side thereof, and with a radius of curvature of eacharc shaped surface being the same as the radius of curvature of thenon-processing region of the columnar work, holding the outercircumferential surface of the columnar work with the holding parts insuch a manner that the holding parts hold the columnar work in thenon-processing region at opposite edges of a respective said processingregion in overlying relation to the processing region and out of contactwith the processing region, to prevent vibration of the columnar workduring processing of the columnar work, by pressure supplied from ahydraulic cylinder and through an oil pressure supply part, and changinga pressure contact position of the holding parts on the outercircumferential surface by releasing pressure of the holding partsthereon to permit rotation of the columnar work.
 10. A method accordingto claim 9, wherein the processing region extends for an angular rangeof the columnar work, and the step of holding includes the step ofholding the outer circumferential surface of the columnar work with theholding parts in such a manner that the holding parts hold the columnarwork in the non-processing region along an angular range around thecolumnar work which is larger than an angular range of the processingregion of the columnar work.
 11. A method according to claim 9, whereinsaid step of providing includes the step of providing first and seconddiametrically opposite said holding parts which come into pressurecontact with opposite sides of the columnar work, and further comprisingthe step of providing a pressure transmission part which is interlockedwith a single hydraulic cylinder for approaching and separating of theholding parts for the vibration stop to and from the work by changingoil pressure.
 12. A method according to claim 9, further comprising thestep of independently interlocking the holding parts for the vibrationstop with the hydraulic cylinder for approaching and separating of theholding parts for the vibration stop to and from the columnar work bychanging the oil pressure.
 13. A method according to claim 9, where thestep of providing includes the step of providing three said holdingparts which come into pressure contact with the columnar work.
 14. Amethod according to claim 9, wherein the hydraulic circuit includes arelief valve in juxtaposition with a solenoid valve for supplying theoil pressure to the vibration stop device.
 15. A method of stoppingvibration of a columnar work during processing of the columnar work, themethod comprising the steps of: dividing an outer circumferentialsurface of a columnar work into a processing region and a non-processingregion in a process stage of the columnar work, with the non-processingregion having a radius of curvature, providing a vibration stop deviceincluding a plurality of holding parts, with each holding part having anarc shaped surface on a pressure contact side thereof, and with a radiusof curvature of each arc shaped surface being greater than the radius ofcurvature of the non-processing region of the columnar work, holding theouter circumferential surface of the columnar work with the holdingparts in such a manner that the holding parts hold the columnar work inthe non-processing region at opposite edges of a respective saidprocessing region in overlying relation to the processing region and outof contact with the processing region, to prevent vibration of thecolumnar work during processing of the columnar work, by pressuresupplied from a hydraulic cylinder and through an oil pressure supplypart, and changing a pressure contact position of the holding parts onthe outer circumferential surface by releasing pressure of the holdingparts thereon to permit rotation of the columnar work.
 16. A methodaccording to claim 15, wherein said step of providing includes the stepof providing first and second diametrically opposite said holding partswhich come into pressure contact with opposite sides of the columnarwork, and further comprising the step of providing a pressuretransmission part which is interlocked with a single hydraulic cylinderfor approaching and separating of the holding parts for the vibrationstop to and from the work by changing oil pressure.
 17. A methodaccording to claim 15, further comprising the step of independentlyinterlocking the holding parts for the vibration stop with the hydrauliccylinder for approaching and separating of the holding parts for thevibration stop to and from the columnar work by changing the oilpressure.
 18. A method according to claim 15, where the step ofproviding includes the step of providing three said holding parts whichcome into pressure contact with the columnar work.
 19. A methodaccording to claim 15, wherein the hydraulic circuit includes a reliefvalve in juxtaposition with a solenoid valve for supplying the oilpressure to the vibration stop device.
 20. A method of stoppingvibration of a columnar work during processing of the columnar work, themethod comprising the steps of: dividing an outer circumferentialsurface of a columnar work into a processing region and a non-processingregion in a process stage of the columnar work, with the non-processingregion having a radius of curvature, providing a vibration stop deviceincluding a plurality of holding parts, with each holding part having aflat surface on a pressure contact side thereof, holding the outercircumferential surface of the columnar work with the holding parts insuch a manner that the holding parts hold the columnar work in thenon-processing region at opposite edges of a respective said processingregion in overlying relation to the processing region and out of contactwith the processing region, to prevent vibration of the columnar workduring processing of the columnar work, by pressure supplied from ahydraulic cylinder and through an oil pressure supply part, and changinga pressure contact position of the holding parts on the outercircumferential surface by releasing pressure of the holding partsthereon to permit rotation of the columnar work.
 21. A method accordingto claim 20, wherein said step of providing includes the step ofproviding first and second diametrically opposite said holding partswhich come into pressure contact with opposite sides of the columnarwork, and further comprising the step of providing a pressuretransmission part which is interlocked with a single hydraulic cylinderfor approaching and separating of the holding parts for the vibrationstop to and from the work by changing oil pressure.
 22. A methodaccording to claim 20, further comprising the step of independentlyinterlocking the holding parts for the vibration stop with the hydrauliccylinder for approaching and separating of the holding parts for thevibration stop to and from the columnar work by changing the oilpressure.
 23. A method according to claim 20, where the step ofproviding includes the step of providing three said holding parts whichcome into pressure contact with the columnar work.
 24. A methodaccording to claim 20, wherein the hydraulic circuit includes a reliefvalve in juxtaposition with a solenoid valve for supplying the oilpressure to the vibration stop device.